Figure 129. Location Of The T/R Offset Trim Pot, R53 - NORCAL NC2030 Manual

Figure 129. Location of the T/R offset trim pot, R53.

This adjustment is not difficult.
- First, set the RIT knob to the center setting. There is a center detent setting for this point.
- Second, with the spot switch turned off (up position), tune in a strong signal and tune it to a
frequency that you want to copy cw at.
- Third, turn the spot switch on (down position). Adjust the trim pot R53 until the strong signal is
zero beat with the receiver.
That is it. Adjusting R53 is setting where the transmitter sends at. You want it to transmit on exactly
the same frequency as the other station. The spot switch helps you check that. Whenever you turn the
spot switch on (switch down), you can zero beat the station and know that you will transmit on his
frequency. Turning the spot switch off (up) will allow you to hear the station at the receive offset that
was set up using trim pot R53. If you want to change this offset because of interference or a change in
your listening preference, the RIT knob can be used to adjust the receiver without changing the
transmitter.
Once again, if you are ever confused as to where you are transmitting, simply turn the spot switch on
(down), and zero beat the station you want to transmit to. A spot switch is a very useful feature to have
in a transceiver. If you ever find that you don't have the default transmit/receive offset (center position)
where you really want it, simply redo the offset procedure above.
At this point, the transceiver is ready to use. If you measure the receiver current drain when connected
to a 12v supply, it should draw between 11 to 12.5 mA. Because a switching supply is used, the current
drain increases as the input voltage drops and decreases as the supply voltage increases. The upper limit
of the supply voltage is 15v. Do not exceed this voltage. The lower limit is 7v. The receiver will work
at a lower voltage than this, but the switching supply output to the keyer becomes unreliable during
transmit. The transmitter will only sometimes work down to 6.2v. Even at this voltage, the output
power will be over 1w.
Norcal NC2030 v5 12-18-05
Page 105 of 128